1. Field of the Invention
This invention relates to a thread cutting device for use in a sewing machine and the like, and more particularly to a thread cutting device for use in an automatic sewing machine and the like.
2. Description of the Related Art
In the conventional type of the thread cutting device, a thread held by a holding member is caught by a moving blade which is rotated by a driving means such as a motor, and is then cut by the cooperation of the moving blade and a stationary blade.
It is desirable that the driving means be miniaturized from the view points of light weight and cost saving since then the sewing machine can be driven with small power. However, if the driving power for rotating the moving blade to cut the thread becomes insufficient, the thread may be pulled between the moving blade and the hold member, due to the tension, the radius etc. of the thread, before the cooperation of the stationary blade and the moving blade can cut the thread. Therefore the moving blade is stopped. The driving means is then stopped by a signal from a detection means and the operator has to restart the cutting operation, and this is very cumbersome.